When you see a stunning piece of worked silver jewellery in a shop, have you ever wondered at the skill which goes into making it? How do silversmiths create those fabulous items we all covet? What techniques are involved, and what tools do they use?
Silversmithing is a craft which takes years to learn, either as an apprentice to a silversmith, or these days in one of the college and university courses which are run in the major jewellery centers of Sheffield, Edinburgh, Birmingham, London and Dublin. Practise is essential to mastery of this wondrous craft, but the basics are achievable by anyone with patience, and the right tools!
There are many techniques which are used by silversmiths, some of which follow:
Piercing – This is the cutting of metal using a piercing saw. Cutting can be functional, to create a basic shape, or decorative, to create a pattern in the metal. If creating a pattern within a sheet of metal, a small hole is drilled in the sheet to allow the blade of the saw to be positioned. The blade is then connected to the piercing saw, which looks like a hacksaw, under tension. Several grades of blade are available, from coarse which allows speed of cutting, to very fine for detailed work. All the blades are delicate and easily snapped, so work must be done slowly. The blade is held vertically, and the metal is moved slowly to make curves or corners. Blades are lubricated by passing them through beeswax to make the cutting smoother. The work is supported on a bench peg which is screwed to a workbench, and has a V cut into it so the area either side of the cut is supported. Small shavings of metal called lemel are collected from under the piercing in a leather or paper cloth, and then recycled into new silver.
Soldering – Soldering silver and other precious metals is somewhat different to soldering for electronics or plumbing purposes. Silver solder (also gold and platinum) melt at a far higher temperature than lead solder, and so a blow torch is necessary. This has safety implications, and creates difficulties for the silversmith, as the temperature needed to melt silver solder is very close to the temperature at which the piece being worked would itself melt. In order to manage the temperatures of the soldering process, soldering and other torch work is usually carried out in darkness, so that the colour of the metal as it heats can be used to gauge the temperature of the piece.
Silver is soldered using silver solder, which contains mainly silver. It comes in various alloy mixes, which alter its melting temperature and its usage. The softest solder, called EASY, has a lower melting point, and is therefore less likely to result in damage to the piece being soldered. MEDIUM has a higher melting point, and HARD has the highest. Pieces where multiple solderings are required use hard solder initially, and work down the grades with subsequent solderings so that each addition does not melt or distort the previous one.
Lead solder is NEVER used with any precious metal or jewellery piece, as the high temperatures involved would cause the solder to run all over the silver, contaminating it and rendering it useless.
Annealing – Annealing is the technique used to soften silver and other precious metals to make then more malleable and easier to work. Malleable metal bends easily without damage to its molecular structure which weakens the piece. The more a piece is worked, the harder and more brittle it becomes, so repeat annealings are used to keep it malleable. Annealing is done with a torch, again in darkness. The work is heated until it glows a soft pinkish red, which is the point just before melting. The piece is then quenched rapidly in a tub of cold water, which freezes the molecules into the alignment they were in when almost molten, and thus makes it easier to work. However, any work with a torch leaves a fire stain on the silver which must be removed before further work is done, so the piece must be pickled.
Pickling – Pickling is the process of placing a fire stained piece of work in an acid bath to remove any oxidisation before working it. Sulphuric acid is most commonly used, although pickling salts which are safer solutions can be bought for the smaller silversmith. The pickling solution is kept warm to speed to process, and once a satisfactory result is obtained the piece is rinsed in running water, then cleaned with pumice powder to remove any last traces.
Shaping – most work will need to be shaped into its finished form. This is done in a variety of ways, dependent on the he shape desired. Tubular shapes such as rings and bangles are shaped on mandrels which are held in a vice, while the annealed metal is hammered with a mallet of wood or hide. Bowls and other curved pieces are domed on leather sandbags and wooden or metal doming blocks, using wooden or shaped metal hammers. Many repeat annealings will be necessary when shaping work.
Polishing – polishing is the last technique used by any silversmith on their piece once the forming work is completed. It is a long process, where a piece is rubbed with progressively finer wet and dry papers to remove any tool marks from working, and then remove marks left by the previous paper used. Once completed it can then be wheel polished, (for larger pieces like bowls) polished with a fine polishing mop on a pendant drill (like a hobby drill), or barrel polished, where it is immersed in a soap solution with steel shot and rotated for 10 minutes or so. The finished result should be smooth and shiny and free of all tool marks.
These are the basic techniques of a silversmith. When learning the art of silversmithing, it is wise to work in a base metal such as brass or copper until you have accomplished a level of proficiency, as its much cheaper when you make mistakes! Design a simple piece on paper, at full finished size. This template is then cut out and glued onto the metal to be worked as a guide. Piercing is done before shaping, which must be done very carefully on a pierced piece as it will have stress points where it will fracture easily. Once you have a pierced and shaped design, either polish it for a glossy finish, or brush it for a matte finish, then wear it with pride.